London, Deadly by Design

Axelle Anderson is back in London and sure that her days of stylish sleuthing are over, until a young fashion photographer named Gavin is mugged and his fashion-blogger sister Tallulah appears on Axelle's doorstep. Tallulah is terrified, because just before his attack, Gavin entrusted her with a mysterious memory stick, and their apartment was ransacked shortly after. The mystery leads Axelle on a chase through the past where she must uncover long-buried clues and figure out which is more dangerous--Gavin's secrets, or whoever is after him.